Arsenal survived a major scare to reach the Europa League last 16, beating Ostersunds 4-2 on aggregate despite a 2-1 loss on Thursday.
Arsene Wenger's side conceded twice within 70 seconds in the first half at the Emirates Stadium and managed only a solitary Sead Kolasinac strike in return, although their 3-0 first-leg win was enough to see them through.
Borussia Dortmund battled past Atalanta in Bergamo to reach the next round, while Atletico Madrid and AC Milan picked up 1-0 wins to ease through comfortably.
There were tragic scenes in Bilbao, though, where a police officer died following clashes between fans ahead of the meeting between Athletic Bilbao and Spartak Moscow.
Complacent Arsenal survive, Celtic crash out
A Calum Chambers own goal and a fine strike from Ken Sema gave Ostersunds a 2-0 half-time lead over Arsenal, leaving the Gunners fearing a spectacular collapse.
Kolasinac's strike just after the break eased some of the anxiety around the Emirates, but Arsene Wenger will have been concerned by the complacent performance, while Ostersunds celebrated a famous win.
Celtic took a 1-0 lead into their second leg with Zenit but offered meek resistance against the Russians, who ran out 3-0 winners to advance 3-1 on aggregate.
Branislav Ivanovic, Daler Kuzyaev and Aleksandr Kokorin got the goals for Roberto Mancini's side.
6 - Graham Potter is just the sixth English manager to win at the Emirates in all competitions after (Alan Curbishley, Phil Brown, Harry Redknapp, Michael Appleton and Garry Monk), but the first to do so in European competition. Future. pic.twitter.com/mUFkE5RVBG— OptaJoe (@OptaJoe) February 22, 2018
Atletico advance, Bilbao win soured by violence
Atletico made light work of their second leg against FC Copenhagen, with Kevin Gameiro's fine strike securing a 1-0 win on the night and a 5-1 triumph on aggregate.
Bilbao lost 2-1 to Spartak Moscow but still advanced 4-3, although their success was marred by violent clashes between fans before kick-off, which saw a police officer involved in attempts to restore order die after suffering a heart attack.
Basque rivals Real Sociedad crashed out with a 4-3 aggregate loss to Red Bull Salzburg, who won 2-1 in Austria thanks to Valon Berisha's second-half penalty.
Meanwhile, a number of Marseille fans missed kick-off due to problems at Braga's stadium, but the Ligue 1 side's 1-0 defeat did not stop them going through 3-1 on aggregate.
Dortmund battle through, AC Milan make it look easy
Dortmund were staring at an away-goals defeat to Atalanta until Marcel Schmelzer struck seven minutes from time in Bergamo, thereby securing a 1-1 draw and 4-3 aggregate triumph.
There was an unsavoury incident involving Michy Batshuayi, though, who took to social media to accuse some home fans of racist abuse after the match.
Milan made light work of Ludogorets, with Fabio Borini's effort sealing a 1-0 second-leg win and 4-0 aggregate success, ensuring a second Serie A presence in the last 16.
|Don´t touch my Grizou – Pogba defends France team-mate|
|Yankees catcher Sanchez likely heading to DL|
|Messi is frustrated and hungry – Mascherano|
|Nainggolan the ´ninja´ Inter were missing, says Spalletti|
|Anthony fires back at Thunder fans unhappy he´s staying|
|MLS Review: New York City edge Toronto in Torrent´s first game|
|Watson shoots 63 to win Travelers for third victory of season|
|Iran contest not all about Ronaldo, insists Santos|
|Truex´s team use tricky strategy to win at Sonoma|
|World Cup 2018: England at home, Brazil´s party and exploding White Nights in St Petersburg|
|Pogba reveals ´issues´ with Mourinho|
|Mascherano plays down rumours of Sampaoli bust-up|
|Sweden winger Durmaz says racist abuse ´passed limit´|
|Morgan hails ´outstanding´ Buttler century|
|Paine to discuss ODI future after England whitewash|
|Cuper unsure of Egypt future as El Hadary nears milestone|
|Koepka ´shutting down´ until Carnoustie|
|Quintero and James plot Colombia´s way through uncharted territory|
|Federer upbeat despite shock Halle defeat|
|Journalists should round on Vettel - Verrstappen|
|Poland 0 Colombia 3: Falcao´s maiden World Cup goal revitalises Pekerman´s side|
|World Cup 2018: Cossack kids, Swan Lake and the Selecao in Rostov-on-Don|
|Maria takes maiden title in Mallorca|
|Hierro: I am 100 per cent the coach of Spain|
|Busquets recognises Iniesta´s burning ambition|
|Denmark v France: Tolisso hoping for second chance|
|Eight-try Wakefield hammer sorry Widnes|
|World Cup 2018: A panda, a tapir and a nightmare for Willy in Nizhny|
|Senegal´s Wague makes African history in World Cup|
|Cilic fights back to beat Djokovic in enthralling Queen´s final|
|Neymar and Suarez among players to send Messi birthday wishes|
|Strength of Senegal and Japan´s determination could trouble England and Belgium|
|Hamilton questions Vettel punishment after Bottas´ race ´destroyed´|
|Brilliant Buttler seals whitewash in Old Trafford thriller|
|World Cup 2018: An egg-and-spoon race, vodka and the Pogbas in Kazan|
|Queiroz tells his Iran players to follow the ´three Rs´ against Ronaldo and Portugal|
|Pizzi calm over Salah threat|
|Japan 2 Senegal 2: Honda gatecrashes Cisse´s party|
|Harden should be MVP ´hands down´, says World Peace|
|Southgate optimistic over Alli recovery for Belgium decider|
|Neymar´s tears no surprise to Fagner|
|Unhappy Renard continues ref rant|
|Wallace takes BMW International title despite Olesen 61|
|Hamilton cruises back to standings summit with France win|
|In-form Kvitova defends Birmingham title|
|Southgate responds to toughest England week in record-breaking style|
|Uruguay not thinking about Portugal or Spain, insists Cavani|
|Coric stuns Federer to claim title in Halle|
|England 6 Panama 1: Kane hat-trick sees Southgate´s side sail through|
|Australia v Peru: Juric keeping the faith as Socceroos chase unlikely last-16 spot|
|England surpass class of 1966 in Panama rout|
|Nigeria v Argentina: All eyes on Messi to rescue final World Cup chance|
|NSW seal Origin series with comeback win|
|World Cup 2018: Stalin´s bunker, a space museum and Serbian specials in Samara|
|Croatia looking out for number one - Lovren|
|Heritage at back of Australian minds ahead of potential Croatia encounter|
|It may be my last World Cup - ´Realistic´ Pogba determined to reign in Russia|
|Lionel Messi´s birthday: What might the Barcelona star wish for?|
|Russia readying Dzagoev for last-16 clash|
|Germany apologised for reaction aimed at Sweden bench|
|Picture this! Sterling starts for England against Panama|
|World Cup 2018: A Russian romp, Maradona and the party in Moscow|
|Happy birthday, Lionel Messi! 10 of the Argentina star´s best goals|
|Modric worthy of Ballon d´Or, says Lovren|
|Sigurdsson ready for Croatia reunion as Iceland go for broke|
|Iceland v Croatia: Dalic to rest stars for Hallgrimsson divorce hearing|
|Men´s tennis will have to ´wake up´ after Federer and Nadal, says King|
|Tennis star Djokovic backs VAR despite Serbia controversy|
|Socceroos have deserved more at World Cup – Skoko|
|Dodgers top Mets in Kershaw´s return from DL|